The Building Research establishment (BRE) carried out tests on fires using concealed (hidden in ceilings) and pendant (suspended under ceilings) sprinklers [118]. The results of the tests indicated that the sprinklers significantly reduced the effect of convected (hot gases and smoke) heat from the fire [118]. However, these sprinklers did not observably improve visibility [118]. The sprinklers generally greatly improved conditions in the case of a television fire in the room by maintaining tenable conditions, i.e., survivable conditions, in terms of toxic effects, reduced the effects of convected heat but produced no observed improvement in visibility [118]. However, in one of the television fires in the study, conditions became unsurvivable in one slower growing fire where a lot of smoke was produced prior to operation of a pendant sprinkler [118]. For all sprinklered and un-sprinklered fires involving table fires the conditions became
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unsurvivable in terms of toxic effects, however, the sprinklers greatly reduced the effects of convected heat but improvement in visibility did not occur [118].
For all the unsprinklered fires in the BRE study, the conditions became unsurvivable/lethal [118]. In these fires the first tenability criterion to be reached was visibility, followed by convected heat and then toxicity effects [118].
The life safety benefit of fitting smoke alarms was clearly demonstrated in the BRE tests. Smoke alarms, fitted in the room of fire origin, responded in 31% to 57% of the time required by sprinklers and well before conditions had become life threatening [118]. Smoke alarms, fitted in adjacent spaces, responded in 43% to 77% of the time required by sprinklers and well before conditions had become life threatening [118].
The document, Scottish Health Technical Memorandum (SHTM): Supplement A (2003) [116], which was prepared by Glasgow Caledonian University for NHS Scotland Property and Environment Forum, provides guidance on the provision of automatic fire control systems in NHS Scotland healthcare premises. In the document [116] it was recognised that there are many occasions where in the event of a fire in patient areas of healthcare premises where:
a) patients cannot be moved or moving them presents a health risk;
b) minimum staffing levels required to move patients are greater than minimum staffing levels required for cost-effective healthcare provision;
The document, Scottish Health Technical Memorandum (SHTM): Supplement A, states that installation of an automatic fire control system provides an approach to addressing a) and b) above [116].
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The report, Fire Safety Policy for NHS Scotland (2008) [114] stated that some 18 healthcare premises in Scotland were known to have fire suppression sprinkler systems installed, with a further 7 projects in which systems have been agreed or are under active consideration as part of the fire safety strategy. Nineteen (19) of these systems were installed, or will be, in hospitals, two are in community healthcare resource centres and a further 4 were installed to protect strategic asset facilities [114]. Fourteen (14) of the systems provided partial protection of high-risk areas and eleven (11) cover, or will cover, the whole premises [114]. Two further systems have yet to be agreed and signed off, and are not counted in these figures. The total number of systems installed or approved for installation is twenty five (25) [114].
The report found that hospitals commonly adopted fire safety engineering solutions in order to permit design flexibility [114]. In such cases prescribed regulatory building standards with respect to fire safety commonly could not be met and the resulting engineered fire safety solutions will invariably, but not always, required the installation of a fire suppression system, most often a water sprinkler system [114]. There is no professional debate about this and it is an internationally recognised and adopted design methodology fully consistent with regulatory requirements and subject to established procedural and compliance arrangements [114].
The Report states that fire safety principles cannot be distilled simply to the provision of fire suppression systems on the assumption that they alone will provide a universal fire safety solution for all hospitals and healthcare premises [114]. Fire safety is achieved by a comprehensive system of measures, both physical and management, that collectively interact to provide a comprehensive system of fire safety, taking account of the building
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design, human behaviour in fire conditions and escape arrangements, management arrangements such as staffing levels, training and fire response, the abilities and disabilities of patients, the fire performance of the materials the building itself is made of, the fire load within the building, the potential ignition sources it contains as well as the measures provided to detect and contain fire when it occurs [114].
The Report states that fire suppression systems, including sprinklers are one component of this mix of measures, and current guidance suggests that design teams should consider the installation of fire suppression [114]. The Report found that fire suppression systems are routinely considered in major projects and installed where identified as essential and that the fire sprinkler and other suppression systems are almost exclusively of recent design and that the adoption rate for sprinklers and other fire suppression systems is increasing significantly [114].
The Report states that in the NHS Scotland document, whether or not sprinklers are appropriate, is currently a matter for relevant architectural and design team professionals who should identify their design considerations and conclusions in a fire strategy for the project in question [114]. Clearly, the provision of fire sprinklers, as part of a fire safety strategy, is project specific on a case-by-case basis, and should be considered alongside the need to comply with statutory standards and the complexity of structural, environmental and management issues [114]. Existing evidence would appear to suggest that fire suppression systems are routinely considered as a component of the design fire strategy in relevant projects [114]. However, the NHS Report states that it should be recognised that it is unlikely that in smaller premises a life safety or economic asset protection case in favour of fire suppression could be justified [114].
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The Report found in its research that there is no empirical evidence to suggest that the traditional fire safety strategy, embedded at the heart of Firecode and in the regulatory building control system, is not effective [114]. Life loss and significant fire injuries are difficult to identify, beyond those unfortunate cases where patients smoke against all advice to the contrary whilst receiving oxygen therapy; or cause self-harming fires in the mental health sector [114]. These situations are very difficult and distressing for staff to supervise and control as patients predisposed to smoke will invariably find a way of doing so [114]. The point of this is that fire sprinklers are unlikely to have a significant impact on the outcome for those unfortunate persons affected by this type of fire. The ‘passive’ nature of fire suppression in the ready state would certainly not reduce the number or frequency of events in these circumstances, and would only become active in response to a significant flaming source already causing life- threatening harm to the individual concerned [114].
The Final Research Report into Sprinkler Effectiveness in Care Homes [31] prepared for the UK Department for Communities and Local Government Buildings Division is concerned with effectiveness of sprinklers in care homes for the elderly. This research found that there was no available information from research to determine whether the severity of a fire at the time the sprinkler operates would be invariably be fatal for the person involved or whether there would be a good chance that they would survive. The Report stated that there was a need to collect more information and evidence to ensure that current assumptions in respect of the life-saving benefits of residential sprinklers stand up to scrutiny [31].
The Report stated that a review of UK fire statistics indicated that most fatalities in care homes arise from occupants accidentally setting fire to bedclothes, night clothes, etc.,
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whilst they are in bed [31]. Many are a result of smokers’ materials. Such fires are often fatal, or cause serious burns [31].
Where a fire has occurred involving either the nightwear or bed clothes of an occupant of a bed, the fire experiments have indicated that sprinklers alone are unlikely to operate quickly enough to prevent the occupant of a bed being fatally injured or suffering very serious injuries from flames and/or heat [31]. However the report found that in most situations where a sprinkler operates, other occupants within the room should survive, since the heat and toxic gases within the room are kept within tenability limits by the sprinkler system [31].
In the earlier study, it was assumed that people involved in a clothing/bedding fire would not survive, so there is very little change to the estimate of sprinkler effectiveness previously established [31].
Whether sprinklers in care homes are cost-effective or not is determined by the installation costs; the findings from this research do not affect this conclusion [31].
The report found that most recent research only generally considered people in the room of origin – it did not differentiate between people in intimate contact with the fire and those remote from it [31].
The Report stated that a smoke alarm fitted in the room will provide early warning of a fire and should alert the occupant and nursing staff to the problem [31]. If the smoke alarm is linked to the sprinkler system, early suppression of the fire is also possible [31]. In such a case, all occupants of the room, including any person in the affected bed,
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should survive [31]. However, such a system would be far more complex (and expensive) than a ‘normal’ sprinkler system, and there would be a possibility of frequent false operations, which could cause distress (and possibly harm) to elderly residents [31].